1. Field of the Invention
The present invention relates generally to convertible and variable length groundwater sampling devices or pumps, and kits of components therefor. More particularly, the invention relates to a plurality of selectively convertible groundwater devices of variable length, such as a single bladder pump, single gas-drive pump or single bailer; or a double bladder pump, double gas-drive pump, or double bailer, and kits of components for constructing same.
The basic groundwater device construction according to the invention includes a plurality of universal components, and any one of a plurality of sets of unique components. The terminology "universal components" as incorporated herein is intended to connote components such as pump bodies, pump body couplers, check valve assemblies, etc., each of which is adapted for interchangeable use in any one of a number of different groundwater sampling or pump assemblies in accordance with the invention. The terminology "unique components" as incorporated herein is intended to connote components which are substantially unique to or specific to a particular type of groundwater lift or pump assembly, such as a bailer, bladder pump or gas-drive pump.
By providing a plurality of different sets of unique components adapted for interchangeable use with the universal components of the invention, the invention affords maximum flexibility in converting from one type of lift or pump device to another merely by substituting one set of unique components for another to be operatively connected with the universal components.
2. Description of Relevant Art
In the art of groundwater sampling it is common to equip a well field with dedicated sampling equipment. The advantages afforded by dedicated equipment include: improved sample integrity; reduced sampling time and cost; elimination of troublesome cleaning procedures; and the ability to equip each well with the most efficient system for that well's specific characteristics. However, changing conditions or requirements often demand the use of groundwater sampling devices other than the device initially dedicated to a given well. For example, when a monitoring well is equipped with a bailer for sample collection, it may become necessary or desirable to use a pump capable of rapid and efficient purging, such as a gas-drive pump. Heretofore, it has been necessary to substitute one groundwater sampling device for another under such conditions, or to equipment the well with two different devices if possible, thus resulting in considerable expense and inconvenience.
There has also been a long-felt need in the groundwater sampling art to overcome the problems encountered by those working in the field in transporting equipment to the sampling site. A single sampling device will not satisfy all sampling needs encountered in the field, as evident when considering the role of groundwater sampling consultants, whose sampling activities take them to many different sites where the range of site-specific conditions demand a variety of different groundwater sampling devices.
Typically, a consultant carries in his truck a variety of discrete groundwater sampling devices, any one of which might be the one best suited for a given site. Because many water sampling sites are not accessible by truck, it is typically necessary for the consultant to manually transport a number of potentially useful sampling devices from his truck, parked some distance away, to the site. To manually transport the different lift devices, tubing, etc. which might be needed at the site may require the efforts of many workers or many trips by one person. Under the messy field conditions often found around sampling sites, a worker may find himself trudging through mud or clay as he hauls parts on repeated trips between the truck and the site. Indeed, he may even have to return to the lab to obtain necessary equipment not carried in his truck.
The following disclosed devices are illustrative of the types of essentially discrete lift assemblies adapted for use under particular site conditions, and thus plagued with the foregoing problems:
NWWA/EPA Manual of Ground-Water Sampling Procedures, published in 1981, discloses various bailers and gas-drive pumps each adapted to be used under particular groundwater sampling site conditions.
U.S. Department of the Interior Geological Survey Report entitled Downhole Pumps for Water Sampling in Small-Diameter Wells, published in 1979, discloses numerous downhole pumps for water sampling under particular small-diameter well conditions.
A catalog of geotechnical, groundwater sampling products from Timco Manufacturing Company, published in March 1982, discloses various groundwater sampling pumps and bailers.
U.S. Pat. No. 3,113,522 issued in 1963 to Coberly entitled "Convertible Fluid Operated Free Pump System" discloses a pump system for oil wells wherein conversion between a duplex and single pump requires removal of one pump, valve and set of passage units and then replacement with a different pump, valve and set of passage units.
The flexibility afforded by the groundwater sampling devices and components according to the present invention overcomes the foregoing problems attendant known lift and pump devices, and in so doing satisfies a long-felt need in the groundwater sampling art. With the present invention, a dedicated groundwater sampling device is not limited to the single type of device initially installed in the well, and instead can be easily and inexpensively converted to another type of device. Also in accordance with the invention, rather than transporting a number of potentially useful discrete devices to a site, a consultant or other user can simply transport a single kit of components which will afford him the flexibility to assemble the correct sampling device at the site itself.
The components according to the invention can be used to make, or to convert between, at least eight different pump or lift devices: 1) a relatively short single bladder pump; 2) a relatively long double bladder pump; 3) a relatively short single gas-drive pump; 4) a relatively long double gas-drive pump; 5) a relatively short single open-top bottom-filling bailer; 6) a relatively long double open-top bottom-filling bailer; 7) a relatively short single dual check valve bailer; or 8) a relatively long double dual check valve bailer. The novel components according to the invention also enable the user to conveniently assemble triple pump constructions, and even longer pump constructions if desired.
Another novel feature of the invention which renders same advantageous relative to known pump constructions is that the pump components can be assembled essentially without the use of tools. Thus, a pump of the desired structure can be assembled and disassembled at the site even while the consultant has protective gloves on. Because groundwater sampling professionals typically wear protective clothing including gloves, the ability to handle the components of the invention without tools or fine parts eliminates the need to remove gloves. Assembly/disassembly substantially without the use of tools also greatly facilitates cleaning and/or replacement of pump components. For example, a bladder assembly of the bladder pump can easily be removed and replaced, and check valves can be disassembled for cleaning, work on the check valve seat, etc.
The present invention thus solves a plethora of persisting problems in the groundwater sampling art which have not heretofore been satisfied by skilled persons.
The universal pump body of the present invention permits a single part to be used interchangeably as a pump body in different sampling devices (bailer, bladder pump, gas-driven pump), and permits convenient connection to additional universal pump body(s) for extending (e.g., doubling or tripling) the length of the pump. The universal pump bodies and other universal components of the invention also provide enhanced versatility, ease of assembly of components, and ease of disassembly and cleaning.